A Review on Ingested Cyanide: Risks, Clinical Presentation, Diagnostics, and Treatment Challenges

Abstract

Cyanide, a metabolic poison, is a rising chemial threat and ingestion is the most common route of exposure. Terrorist organizations have threatened to attack the USA and international food and water supplies. The toxicokinetics and toxicodynamics of oral cyanide are unique, resulting in high-dose exposures, severe symptoms, and slower onset of symptoms. There are no FDAapproved therapies tested for oral cyanide ingestions and no approved intramuscular or oral therapies, which would be valuable in mass casualty settings. The aim of this review is to evaluate the risks of oral cyanide and its unique toxicokinetics, as well as address the lack of available rapid diagnostics and treatments for mass casualty events. We will also review current strategies for developing new therapies. A review of the literature using the PRISMA checklist detected 7284 articles, screened 1091, and included 59 articles or other reports. Articles referenced in this review were specific to risk, clinical presentation, diagnostics, current treatments, and developing therapies. Current diagnostics of cyanide exposure can take hours or days, which can delay treatment. Moreover, current therapies for cyanide poisoning are administered intravenously and are not specifically tested for oral exposures, which can result in higher cyanide doses and unique toxicodynamics. New therapies developed for oral cyanide exposures that are easily delivered, safe, and can be administered quickly by first responders in a mass casualty event are needed. Current research is aimed at identifying an antidote that is safe, effective, easy to administer, and has a rapid onset of action.

The two faces of cyanide: an environmental toxin and a potential novel mammalian gasotransmitter

“…In humans, the acute oral lethal dose of KCN is approximately 200 mg. In the gaseous form, the Immediately Dangerous to Life or Health value for inhaled hydrogen cyanide is 50 ppm [11][12][13][14][15].…”

Presence of pesticides, mercury and trihalomethanes in the water supply systems of Ibagué, Colombia: threats to human health

“…Organochlorine compounds can resist biodegradation, accumulate in the environment and become persistent organic pollutants that have been detected in animal and human tissues. It can have adverse effects on the endocrine system affecting the production of hormones, such as thyroid and sex hormones; in the nervous system it can cause neuronal effects and dysfunction of neurotransmitters and affect liver function besides being potentially mutagenic and carcinogenic (Hendry-Hofer et al, 2019;Nicolopoulou-Stamati, et al, 2016;Zaragoza-Bastida et al, 2016).…”

Severe lactic acidosis from acute cyanide poisoning after intentional amygdalin ingestion in a teenager

“…Interestingly, several meta-analyses found that the vast majority of cyanide toxicity cases are caused by ingested forms of the toxin. 1 Though uncommon in the United States, case reports in more tropical countries exist in pediatrics regarding oral cyanide toxicity. Among those, several describe ingestion of apricot kernels, bitter almonds, and cassava plant leading to similar symptomatology of vomiting and altered mental status.…”